ci: pin gcp-docuploader to a working version (#9076)
ci: pin gcp-docuploader to a working version (#9076)

The latest release of gcp-docuploader does not work (version mismatches
with Protobuf). This pins the script to use an unreleased version, that
is ugly, but works.
googleapis/google-cloud-cpp,googleapis/google-cloud-cpp,googleapis/google-cloud-cpp,googleapis/google-cloud-cpp